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CVE-2026-21243

Estado: AnalizadaAlta (7.5)—

Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

Vector CVSS AV:N/PR:N/UI:N indica acceso remoto sin autenticación ni interacción: T1190. El impacto es DoS (A:H) contra servicio LDAP remoto accesible en red: T1499.004 (Denial of Service - Application Exhaustion)

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Filter Network TrafficVulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkApplication Isolation and Sandboxing

Tecnologías afectadas (4)

Microsoft — Windows Server 2019Microsoft — Windows Server 2022Microsoft — Windows Server 2022 23h2Microsoft — Windows Server 2025

CWE

Referencias

JSON original (NVD)

Mostrar
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          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "none"
            },
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              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
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          "version": "2.0.3",
          "timestamp": "2026-02-11T15:27:48.672826Z"
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  "published": "2026-02-10T18:16:25.480",
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21243",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "secure@microsoft.com"
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  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "source": "secure@microsoft.com",
      "description": [
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          "value": "CWE-476"
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  "descriptions": [
    {
      "lang": "en",
      "value": "Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network."
    },
    {
      "lang": "es",
      "value": "Desreferencia de puntero nulo en LDAP de Windows - Protocolo ligero de acceso a directorios permite a un atacante no autorizado denegar el servicio a través de una red."
    }
  ],
  "lastModified": "2026-06-17T10:18:20.897",
  "configurations": [
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